About Kavli ENSI

“If we can understand the principles of energy conversion at this very small scale, we can come up with new energy technologies that may look very different from the ones we have now. “

-Kavli ENSI Founding Director Paul Alivisatos

We know a lot of about how to harness energy from oil, wind, and the motion of water through a dam, and energy has become central to our modern civilizations. Our current energy-generation schemes, however, seem crude in comparison to the elegant systems nature has evolved over millions of years. Those natural systems serve as inspiration for researchers at the Kavli Energy NanoScience Institute (ENSI), who aim to be part of creating powerful new approaches to energy conversion, utilization and efficiency.

THE IMPORTANCE OF ENERGY

Societies need access to clean, affordable energy in order to raise and maintain their standards of living. The Kavli ENSI’s focus on both short- and long-term thinking couldn’t have arrived at more opportune time. The world’s demand for energy has been steadily increasing. The Kavli ENSI, founded in 2013, entered the scene just after new technologies and computing power enabled researchers to investigate questions that were previously out of bounds.

Kavli ENSI researchers are exploring fundamental issues in energy science, using cutting-edge tools and techniques developed specifically to study and manipulate nanomaterials – stuff with dimensions the size of molecules, about 1,000 times smaller than the width of a human hair. The physical world seems to deal with energy differently at this scale. Kavli ENSI researchers believe that understanding these phenomena will open door to new approaches to energy.

Kavli ENSI founding director and UC Berkeley Executive Vice Chancellor and Provost Paul Alivisatos (left) in his laboratory. Photo by Roy Kaltschmidt, LBNL

FACULTY

The Kavli ENSI is a team of 23 world-class scientists from UC Berkeley and Berkeley Lab from physics, engineering, materials science and engineering. Together, they aim for two complementary goals that inform and build on each other: 1) gain a deeper understanding of how biological molecules capture and convert energy, and 2) engineer nanodevices that mimic and improve on nature’s tricks, using materials ranging from graphene and metal oxide frameworks to nanowires and nanolasers.

Many Kavli ENSI members have worked on nanoscience projects as varied as photosynthesis, nanomachine-enabled virus reproduction, nanotube motors and devices, engineered nanostructures, and ways to manipulate the movement of heat. They often collaborate with their peers, and sometimes with researchers in other disciples. Yet their collaborations tend to focus on the same types of problems. Someone working on nanotubes will collaborate with someone else working on nanotubes.

At Kavli ENSI, that nanotube researcher has the opportunity to interact with researchers who work on biological nanomachine motors. Researchers who want to control the flow of heat in nanoscopic devices get to talk with scientists who have faced similar challenges building devices to control the flow of light and electrical charges.

This kind of collaboration is vital to making real change in the way deal with energy. “We’re like a team here,” says Felix Fisher, Assistant Professor of Chemistry and an ENSI researcher. “You take inspiration from people working in other areas, and get expertise from many brilliant minds. Only a group of people working together like this can actually address the bigger picture of energy.”

ENERGY AT THE NANOMETER SCALE

ENSI Co-Director Paul Alivisatos explains that much of today’s energy research focuses on improving well-known technologies, such as batteries, liquid fuels, solar cells and wind generators. On the nanoscale, however, energy is captured, channeled and stored in totally different ways dictated by the quantum mechanical nature of small-scale interactions. Scientist have yet to unravel the foundational issues of how energy is converted to work on that scale.

ENSI researchers are moving toward that goal. Work by UC Berkeley and Berkeley Lab chemist Graham Fleming has shown, for example, that when leaf pigments capture light in the form of photons, electrons are excited and interact in a coherent way not seen at larger scales. This quantum coherence could potentially be incorporated into nanoscale artificial systems to produce energy from sunlight more efficiently.

While studying nanoscale motors inside cells, UC Berkeley physicist Carlos Bustamante and Berkeley Lab theorist Gavin Crooks discovered that energy flow does not always follow the standard rules of macroscopic systems. Nanomotors can sometimes move backward, for example, akin to a ball rolling uphill briefly. Such quantum weirdness confers some real benefits to biological motors, and these benefits might be replicated to create more efficient nanomachines or self-regulating nanoscale energy circuits.

Other Kavli ENSI scientists plan to investigate how heat flows in nanomaterials and whether the vibrational energy, or phonons, can be channeled to make thermal rectifiers, diodes or transistors analogous to electronic switches in use today; develop novel materials, ranging from polymers to cage structures and nanowires, with unusual nanoscale properties; or design materials that could sort, count and channel molecules along prescribed paths and over diverse energy landscapes to carry out complex chemical conversions.

Biophysicist Carlos Bustamante with the optical tweezers setup used to measure nanomotors strength. (Credit: Lawrence Berkeley National Lab - Roy Kaltschmidt, photographer)

THE KAVLI ENSI's RESEARCH IS FOCUSED AROUND SIX THEMES: